Shock swept the world Monday after Israeli commandos stormed a flotilla of aid ships bound for the Gaza Strip, killing at least 19 activists. The UN's rights chief Navi Pillay said she was "shocked" at the violence of the raid while the European Union demanded a full inquiry from Tel-Aviv.

Turkey, who stood behind the flotilla warned of "irreparable consequences" to bilateral ties with Tel Aviv. "This deplorable incident, which took place in open seas and constitutes a fragrant breach of international law, may lead to irreparable consequences in our bilateral relations," a written statement, cited by AFP, said. "By targeting civilians, Israel has once again shown its disregard for human life and peaceful initiatives," Turkey said.

On his part, Iran's President Mahmoud Ahmadinejad denounced the raid as "inhuman Zionist regime action."

Palestinian president Mahmud Abbas announced three days of mourning over the "massacre," while the Arab League chief Amr Mussa called it a "crime."

The European Union demanded Israel mount a "full inquiry," as foreign affairs chief Catherine Ashton demanding "an immediate, sustained and unconditional opening" of crossings to Gaza Strip. Spain -- the current European Union president -- Sweden and Greece summoned the Israeli ambassadors to their capitals to demand explanations, with Madrid slamming the operation as "unacceptable".

Greece, which had some 30 nationals on board the flotilla, also withdrew from joint military exercises with Israel in protest at the brutal operation.

French Foreign Minister Bernard Kouchner stated he was "deeply shocked" by the Israeli raid and insisted "nothing can justify" such violence. Germany's Foreign Minister Guido Westerwelle also said he was "deeply concerned" about the deaths.